Wipe the gunk out of your eyes [LWN.net]

Wipe the gunk out of your eyes

Posted Oct 4, 2007 6:43 UTC (Thu) by mingo (subscriber, #31122)
In reply to: Wipe the gunk out of your eyes by filker0
Parent article: Memory part 2: CPU caches

Yes, we're stuck with the i86 lineage, and we will suffer performance ceilings because of it.

Yes - but this statement ignores the complete economic picture: it's not just the hardware that matters, but the total stack that is in a computing solution. Nobody buys just the raw hardware - the software is an inextractable part of the equation.

So once you take the cost of writing and supporting software into account too, applied to general computing problems that computers are used for, you will realize that today the hardware is not the main limiting factor but humans are. Most software is running a few orders of magnitude slower than it could run on the hardware.

The platform that is slightly slower but offers superior programmability - especially for something as hard to grok for humans as parallelism and/or cache coherency - will continue to be the most economic choice in all mainstream uses of computers. (and will continue to use the resources it earns from the mainstream to chip away on most of the remaining niches)

The trick is to maintain the right balance between programmability of a platform and raw physical performance - and the x86 space has done that pretty well over the years. (combined with the fact that the x86 instruction set has become a de-facto bytecode - so RISC never had a chance even technologically.)

(If only performance mattered then customers would buy hardware by sending complete chip designs and hard disk images to manufacturers, optimized to their business problem, which would then be assembled from scratch. There would be no uniform 'instruction set' per se. We are still decades (or more) away from being able to transform arbitrary, abstract business problems into actual hardware in such a pervasive way, without having any common platform layered between them. The moment you have even just a single persistent layer between the business problem and the hardware (be that layer controlled by the customer or by a manufacturer or by the market), platform thinking takes over and raw performance takes a backseat.)

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Wipe the Windows out of your eyes

Posted Oct 5, 2007 17:27 UTC (Fri) by hazelsct (guest, #3659) [Link]

...this statement ignores the complete economic picture: it's not just the hardware that matters, but the total stack that is in a computing solution. Nobody buys just the raw hardware - the software is an inextractable part of the equation.

This is why free software is superior, *all* of our software already runs on *all* the hardware (e.g. 95%+ of Debian builds on all eleven arches), and very well at that! "Programmability" is bunk, all modern CPU architectures are programmable, we're just the only ones bothering to program all of them -- or rather, the only ones open enough to let people adapt our programs to all of them.

So when Sun starts selling its 8-core 8-threads/core Sparcs next year, Solaris, Linux, and maybe one or two BSDs will be there, Windoze and MockOS will not. GNOME, KDE, Compiz Fusion, Croquet, Looking Glass, Second Life, Sugar, etc. will be there; Aero, Carbon, and any 3-D environment they dream up will not. We will have better servers, and better immersive 3-D performance, the games will follow, and it will be over for MS and Apple.

Okay, maybe it won't happen quite that fast. But follow the trends: we were first on Itanium (but who cares?), first on AMD64 (and AMD credits us with driving that platform's success), our software is all over ARM where only a minuscule fraction of Microsoft's is (on "Pocket PC" or "Windows Mobile" or whatever they're calling it now). When the next CPU architecture breakthrough comes, we'll be there and they'll need to play catch-up, again -- hopefully the hardware won't wait for Microsoft this time.

Speaking of which, this is also how DEC fumbled the marketing of Alpha -- they waited for MS to have NT ready before releasing it, and lost more than a year in that wait. They should have bypassed NT, released earlier with VMS and OSF/1 (or Digital Unix, etc.), dominated the workstation/server market, then used Linux on the low end to ramp up the volume and stay faster than Intel.

MS is darned lucky that modern x86-compatible CPUs run 64-bit code somewhat fast with low power consumption. Otherwise Linux on Alpha/Itanic/PPC64 on the high and end ARM on the low end would have eaten their lunch. But then, we're doing that *now* on handhelds and smart phones, we're on Cell and they're not, and we'll beat them to the 64-way Sparcs!

Resistance is futile. World domination is inevitable.

Not Windows specific

Posted Oct 11, 2007 19:51 UTC (Thu) by renox (subscriber, #23785) [Link]

Uhm, the next architecture clash I expect to happen is not what you're waiting for (a new architecture gaining some marketshare) but low power x86 cores gaining over ARM in the 'intelligent phone' space.

Plus even free software has portability issues: the OLPC doesn't use an x86 for nothing..